Electromagnetism Definition and 853 Threads

Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force is carried by electromagnetic fields composed of electric fields and magnetic fields, and it is responsible for electromagnetic radiation such as light. It is one of the four fundamental interactions (commonly called forces) in nature, together with the strong interaction, the weak interaction, and gravitation. At high energy, the weak force and electromagnetic force are unified as a single electroweak force.

Electromagnetic phenomena are defined in terms of the electromagnetic force, sometimes called the Lorentz force, which includes both electricity and magnetism as different manifestations of the same phenomenon. The electromagnetic force plays a major role in determining the internal properties of most objects encountered in daily life. The electromagnetic attraction between atomic nuclei and their orbital electrons holds atoms together. Electromagnetic forces are responsible for the chemical bonds between atoms which create molecules, and intermolecular forces. The electromagnetic force governs all chemical processes, which arise from interactions between the electrons of neighboring atoms. Electromagnetism is very widely used in modern technology, and electromagnetic theory is the basis of electric power engineering and electronics including digital technology.
There are numerous mathematical descriptions of the electromagnetic field. Most prominently, Maxwell's equations describe how electric and magnetic fields are generated and altered by each other and by charges and currents.
The theoretical implications of electromagnetism, particularly the establishment of the speed of light based on properties of the "medium" of propagation (permeability and permittivity), led to the development of special relativity by Albert Einstein in 1905.

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  1. BeBattey

    Electromagnetism: Trouble understanding the D field

    I've just finished my first term in an undergrad electromagnetism course using Wangsness as a textbook and we ended on the displacement field. I feel like Wangsness doesn't give a very good explanation of what the whole point of it actually is, and I still don't quite understand how to use it...
  2. S

    Conservation of angular momentum (electromagnetism)

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  3. F

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  4. C

    Why using diff. forms in electromagnetism?

    In electromagnetism we introduce the following differential form \begin{array}{c} \mathbb{F}=F_{\mu \nu}dx^{\mu}\wedge dx^{\nu} \end{array} Then the homogeneus Maxwell equations are equivalent to: \begin{array}{c} d\mathbb{F} = 0 \end{array} And is nice, but what purpose does this have...
  5. J

    Is Relativistic Electromagnetism Affecting a Test Charge Above a Moving Wire?

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  6. STEMucator

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  7. D

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  8. T

    Conceptual questions about electromagnetism inside

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  9. M

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  10. M

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  11. A

    Understanding magnetism and electromagnetism

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  12. Y

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  13. P

    Electromagnetism, finding magnetic field strength

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  14. P

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  15. P

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  16. P

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  17. P

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  18. Spinnor

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  19. M

    Learning curve of Electromagnetism?

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  20. 4

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  21. J

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  22. M

    Electromagnetism - Dielectric and Various Cavities

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  23. H

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  24. C

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  25. J

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  26. D

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  27. B

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  30. S

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  31. jtbell

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  33. C

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  34. V

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  35. N

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  36. M

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  37. K

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  38. S

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  39. T

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  40. V

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  41. Jalo

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  42. S

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  43. S

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  44. M

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  45. C

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  46. N

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  47. R

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  48. K

    Seeking Help with Electromagnetism: Understanding 'Cancelling the Singularity

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  49. S

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  50. S

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